Infant behavior in Bolivian squirrel monkeys (Saimiri boliviensis boliviensis) was studied to understand the infant?s role in establishing partner preferences. Partner selection is determined by which animal initiates and/or terminates an interaction. Future encounters between pair members are influenced by the positive or negative nature of a partner?s response. This study focused on infant and partner responses to behavior associated with partner selection. Ten Bolivian squirrel monkey infants were observed for three 15-minute focal animal observations per week for the first six months of life. During the first two months, only animals accepted by the dam were available to the infant. By month three, animals rejected by the infants showed significantly lower interaction rates compared with animals that received positive responses. The infants had significantly reduced approaches to partners who had rejected them. Infants continued to interact with juveniles and adults based on the partner?s positive responses. Social integration was found to begin during the first six months of life through a series of accepted and rejected dyadic interactions.